Brewer&#39;s pitch.



UNITED s Es PATENT OFFICE.

, oHA'RLEsN. FORREST, OF BROOKLYN, NEW YORK, ASSIGNOR TO THE BARBERASPHALT PAVING COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION OFWEST VIR- GINIA.

' Specification of Letters Patent.

. BREWERS PITCH.

Patented Jan. 28, 1908.

Application filed December 22. 1906. Serial No. 34r9.1'75.

'To allwhom it may concern:

Be it known that I, CHARLES N. FORREST, a citizen of the United States,and a resident of Brooklyn, in the county of Kings and State-of NewYork, have invented certain new" and useful Improvements in BrewersPitch, of which thefollowing is a specification.

Malted liquorsrequire peculiarly clean an cleansable receptacles; andyet owing to trade usages, empty beer pabka'ges .or kegs after beingexposed to atmospheric influences and dust during transit, must be usedover again, notwithstanding that the dregs remain in them, and usuallyhave become sour or dirty. For the purposes of facilitating the cleaningof'such receptacles for malted li uors and for. the purpose'of'keepingthem iologically clean and free from taste or odor, it is customary toapply to the inner surfaces of brewers wooden or metal recep' tacles(such as vats, barrels and kegs in which beer, ale and other maltliquors are stored while agingin the brewery or being served to thetrade), a coating which is commonly called brewers pitchf Thesubstanceis, perhaps, not a true pitch; but it will be understood that I use thename brewers pitch in its trade-rather than in itsscientificdesignationas covering any substance suitable for thepurposes of coating thesereceptacles, and having the functions which I have described.

The ordinary brewers itch heretofore employed is a'preparationofholophony, or common rosin, which is applied to the inside of thekegs, by heating and spraying it upon the surface. 1 It'tends topreserve the wood from decay, but its main purpose'is to pro-- vide asmooth and, therefore, cleansable surface for the inside of the kegto'which impurities will not adhere, and from which all contaminatedcontents; may easily be removed. Colophony has the further desirableproperty-of being mildly antisepticl A difhculty which has heretofore'been experienced with this brewers pitch results from the fact. thatcolophonyis acted upon by water, and is exceeding soluble in alcohol,con sequently the coating applied to the interior of the keg is soondisintegrated and has to be removed. Furthermore, the extended use of0010 hony in other arts, conjoined with the dep etion of the pineforests, has rendered it an expensive material, making it difficult thesame economica I have discovered that a brewers pitch may be made from anative bitumen which will have all the desirable properties of that heretofore made from colophony, with the addi tional advantage of a muchlonger life, result ing from the fact that the native bitumens are notsoluble in either water or dilute alcohol- The native bitumens Which Ihave found to be suitable as the basis for the preparation of myimproved brewers pitch, are those which are classified as the hardnative bitumens, particularl manj ak, (a hard bitumen found in the Isands of Barbadoes),. gilsonite, grahamite, and wurtzilite. These arehard, tasteless, odorless and comparatively free from mineral matter(not more than one per cent. in-which respect they differ from otherbitumens which would therefore be unsuitable for the purposes of myinvention.

In order to prepare a brewers pitch from these bitumens, I combine thebitumen with a suitable temperingagent, and, also, preferably, with asuitable antiseptic substance.

superior to t ose heretofore employed inall the properties which aredesired in this sort of an article. malt liquor indefinitely without,.onthe one on the other hand, Without imparting any odor or taste thereto.

these hard native bitumens, the material may be cheaply prepared. I

In practicing my invention 1 fuse in a suitable vessel, by means'ofheat, one or more of the hard native bitumens having the characteristicsenumerated above, and add to it a suitable tempering agent. The functionof the tempering agent is to impart to Qthebitumen the requisitephysical qualities is to say, the temperature "at which the bitumenbecomes sufficiently fluidto allow of its must be a comparatively lowone, say about .150 or 200 degrees F. and yet the composition must atordinary atmospheric temperature, be hard but not excessively brittle;.it must possess some ductility, but must not soften or flow undersummer heat; it must It will remain in contact with I Furthermore, onac-- count of the extensive natural deposits of for brewers to supplytheir requirements for When thus. repared my brewers pitch is hand,being dissolved or disintegrated; and,-

,to adapt it for use as a brewers pitch, that application to-theinterior of the receptacle be adhesive}. and it must present smoothand'glassysurface, which is readily cleansedl These. ualitiesarethosewhich are possessed natura y by the hard bitumen except the,capacity to be readily liquefied.

v t will therefore, be seenthat the tempering agent must be, one which;lowers thez temperaturej hy the addition of which to the bitumen. these.needed qualities may be im arted. I prefer,-however, to-employ what islrn at which thelbitunien becomes fluid without substantially softeningit at 'atmospheric temperatures or otherwise altering itsva'luablecharacteristi'csj I have'foundi that .w'ax orwax tailings arethe most suitable forms, of tempering-agents OWIl ' ascwaxitailinga,(sometimes called ""p etr'o .leu'rrnw'ax, or still wax), a substance whchis" the tillation: of 1' product of the destructive dis-;petroleunii'f'v As a tempering agent, either of -fthese materials may.be employedlwithout' ..di1ut1on.,--or, maywbeicombined with petroile mpitch, candle. tar (stea'rin pitch) or other y-p'roduct tars orbituminous substanoes,"these combinations-being dependent to some.extent, upon" the variations, in the selection "of the hardgnativebitumens which are usedasthe basic material,- vand which,vary,accorclmgto the availablei'supply of .In addition tofithetempering-agent, I find" thatit'isdes'irable'toadd a certaina'mount offa mixture of colophony' and rosin oil; This imparts its antisepticqualities to the pitch.

Usually a mixture in about equal parts of colophony and "rosin" oil willbe suitable,=th'e proportions varyingaccording to the viscosityof-therosin' oili I While the proportions ofthe components which I havementioned may vary, I find that I secure the best, results by combiningfrom thirty-fiye per cent. to fifty per cent. of

. ahard native b tumen with fromfifteen to twenty-five per cent. of thetempering agent (such as Wax tailingsior wax tailings combined withother substances); and thirtygfiye to forty per cent. of' a mixture ofcolophony and rosin oil. The brewers pitch thus prepared possesses allthe desirable properties required fora brewers' pitch. It melts to'aroper consistency for application at a mo erate temperature so that itmay be easily'applied by spraying within the rece tacle; it provides t esmooth, hard, durab e, elastic, cleanly and cleansable coating which 1srequired; and is also mildly antiseptic, lacking I any taste oi odor andhas'alonger life than the pitches heretofore employed by. reason of itsi'ns'olubility in both waterta'nd alcohol.

. -When it is desired toapply' this 'pitchto iarge'ta'nks Q1 vats,orother receptacles, J

e, denser portions of paraffin men; a temperm' 877,888 the which cannotbe'reached 'by the pitching devices heretofore referred to, the itch maybe diluted inan equal proportion yweight of turpentine or petroleumspirits, bringrng it to a consistency which will ermit it being appliedwith a paint brush. gbviously, under thesecircumstances, the turpentinebe- ;in extremely volatile, acts merely as a ye icle and largelyevaporates, and plays no substantial part 111 the composition of thebrewers pitch.

f I am aware that it has heretofore been [proposed to combine Trinidadasphalt (Which is a-native bitumen containing about 35% of mineralmatt'er) with a suitable fluxing agentgfor the formation-of a waterproofcomposition. But the resence of the nuneral matter in Trinida asphalt,as well as itscharacteristic odor and taste, render such a compositionWholly-unsuitable for use as a brewer s pitch.

:Having Y thus described my inyentio n I able teinpering' agent composedof wax tailings com ined with a petroleum pitch. v

; 4, A brewer s pitch comprising a hard-bitutem 'erature at 'w ich thebitumen becomes flui but which does not render it softat atmospherictemperatures; and an antiseptic substance.

5. A bre'we'rs pitch comprising a hard bitu.

men as a base; wax tailings as a-tem ering agent; anda mixture ofcolophony an rosin 011; all combined in about the proportions specified.

6. A brewers pitch comprising a hard na 'tive bitumen suchas manj'ak,gilsoni te,

grahamite or wurtzilite; an a temperlng agent which lowers thetemperature at'which -t e bitumen becomes fluid but which does notrender it soft tures.

signedmy name,iat Long, Island City, l lew York, this ZOthday ofDecember, 1906.

i a I CHARLES N. FORREST.

Witnesses:

CLIFFORD Rrcn annson, M. P. 'ENNrs. 1

1,15 at atrncispheric t'empera- In testimony whereof, have hereunto .1agent which lowers the

